The Department of Agriculture is authorized to purchase passenger-carrying automobiles through the Department of Administrative Services for the use of Department of Agriculture employees in the performance of their official duties; and the Department of Agriculture is expressly authorized and empowered to purchase and maintain such passenger-carrying automobiles for such purposes. The number of such automobiles and regulations governing their use, utilization, and replacement shall be determined by the Department of Agriculture, subject to any budgetary or other restrictions enacted by the General Assembly. The Department of Agriculture is authorized to contract with the Department of Administrative Services for any automobile or motor vehicle services provided for in this article.